/*
 * Copyright 2013-2016 Sergey Ignatov, Alexander Zolotov, Florin Patan
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.goide.usages;

import com.goide.psi.GoFunctionOrMethodDeclaration;
import com.goide.psi.GoNamedElement;
import com.goide.psi.GoTypeSpec;
import com.intellij.openapi.project.Project;
import com.intellij.psi.PsiElement;
import com.intellij.psi.util.PsiTreeUtil;
import com.intellij.usages.PsiElementUsageGroupBase;
import com.intellij.usages.impl.FileStructureGroupRuleProvider;
import com.intellij.usages.rules.PsiElementUsage;
import com.intellij.usages.rules.UsageGroupingRule;
import org.jetbrains.annotations.Nullable;

public class GoFileStructureGroupRuleProvider implements FileStructureGroupRuleProvider {
  public static final UsageGroupingRule USAGE_GROUPING_RULE = usage -> {
    PsiElement psiElement = usage instanceof PsiElementUsage ? ((PsiElementUsage)usage).getElement() : null;
    GoNamedElement topmostElement = PsiTreeUtil.getParentOfType(psiElement, GoTypeSpec.class, GoFunctionOrMethodDeclaration.class);
    if (topmostElement != null) {
      return new PsiElementUsageGroupBase<>(topmostElement);
    }
    return null;
  };

  @Nullable
  @Override
  public UsageGroupingRule getUsageGroupingRule(Project project) {
    return USAGE_GROUPING_RULE;
  }
}
